Cap and shell fastening



July 29, 1930. I L, JR 1,771,636

GAP AND SHELL FASTENING .Filed May 28, 1929 Patented July 29, 1930UNITED "STATES.

HARVEY HUBBELL, JR, OF BRIDGEPORT, CONNECTICUT CA]? AND SHELL FASTENINGApplication filed May 28,

This invention relates to the enclosing shell for lamp sockets and thelike, particularly to the means for connecting the cap and body sectionsofthe shell together, andhas 6 for an object to provide an improved capand shell construction which will give a smooth plain exterior to thecap and in which the body and-skirt portions of the cap may be made inone piece.

It is also an object of the invention to provide an improvedconstruction which will positively lock the cap and body sectlons oftheshell together with a connection which will carry considerableweight, but which may be easily unlocked to permit separation of the capand body.

It is a further object of the invention to provide a cap having aprotected and sharply defined locking shoulder as contrasted with theprior art wherein said portion is unprotected and hence is not sharplydefined, and thus the present inventionprovides a better and moredurable device and one in which the locking means between the cap andshell will sustain a greater strain without failing or separating.

With the foregoing and other objects in view, I have devisedthe'construction illus trated in theaccompanying drawing forming a partof this specification.

In this drawing Fig. 1 is a side elevation of a lamp socket withportions of the cap and body section broken away to show the connectionsbetween the cap and body in section, the section being substantially online 11 of Fig. 2.

Fig. 2 is a transverse section substantially on line 22 of Fig. 2 andshowing the insulating body for mounting the switch and lamp contacts inelevation.

Fig. 3 is a partial side elevation and partial section of the capindicating the deep and shallow notches formed in the edge of theskirt.v

Fig. 4 is a perspective view of the-lower part of the cap showing thefree edge portions between the deep notches folded toward the inner sideof the cap.

Fig. 5 is a perspective view of the upper end of the body of the shell,and

1929. Serial No. 366,624.

securing means on the plane of Fig. 1, showing the free edge beveled andon an enlarged scale.

, The shell illustrated is shown as enclosing the elements of a lampsocket having a switch operated by a pull chain. The detailedconstruction of this switch is not shown as it forms no part of mypresent invention. The shell comprises a cap section 10 and a bodysection 11 made of sheet metal in the usual 1nanner,and enclosed by thebody section is the block 12 of insulating material in which are mountedthe switch elements, not shown, and which also carries the screw shelland central lamp contacts not shown. It will, 7 of course, be understoodthat while I have shown thisshell connection as applied to a lampsocket, it is by no means limited to use therewith, as it may be usedfor enclosing shells of depending switches and like devices. Thisinsulating block carries the usual binding post screws 13 for connectinglead wires 14 in the usual manner. The upper portion of the cap is linedwith a suitable fibre or other insulating lining 15 and the body'of theshell is lined with a similar lining 16 enclosing the works of thesocket. The body portion of the shell also has the usual notch 17extending longitudinally from the free end thereof for passage of theguide 18 for the pull chain 19 for operating the switch, or the key oroperating the switch if a key operated switch is used.

The cap is provided with a substantially cylindrical skirt portion 20,and it is of somewhat larger diameter than the body of the cap toprovide a shoulder 21 on the inside of the cap spaced a suitabledistance from the free edge of the skirt. This free edge is providedwith, deep notches 22 and shallow toward the body of the cap, as clearlyindicated in Fig. 4,:preferably toward the inner wall of the cap so thatthe-y will be out of sight in the finished shell. It will be apparentthat in this position the'bottoms of the shallow notches 23 form sharplydefined recessed shoulders adjacent the inner wall of the cap and spacedinwardly from the free edge of the cap, and that the portions 24carrying these shoulders are separated by the notches 22. lVhen thisfree edge is being folded over, the folding tool has a tendency to'bevelthe free edge as at 25, Fig. 6 making the end 25 an unsatisfactoryshoulder for locking use. The shoulder at 23, however, is protected fromthe beveling effect of the folding tool and hence remains sharply de-'fined with a sharp edge and forms a recessed shoulder for satisfactorylocking use. It will further be noted in Fig. 4 that the deep notcheshave become openchannels 22, and that these channels are open at bothends,

while the shallow notches have provided the recessed shoulders 23. Itwill be also noted that it is comparatively easy in manufacture 1 forthe folding tool to fold over portions 24 between the deep notches 22.

The body section 11 is adapted for telescoping engagement with the cap,as shown in F 1. Adjacent the free end of this section it is providedwith outwardly extending lugs 26 which are preferably arranged in pairson substantially diametrically opposite sides of this body section, onepair being adjacent the notch 17 so that the wall of the body sectioncarrying these lugs is'yieldable inwardly. This is clearly shown in Fig. 5.

, A convenient way of forming these lugs is to form short transverseslits or cuts 27 in the body section and then force the wall ofthesection above the slit outwardly. This will give a 'sheulder28 on thelower end of the lug which extends outwardly from the face of the body.The lugs of each pair are spaced from each other substantially thedistance between two of the recessed shoulders '23 or a multiplethereof. Also between the lugs of one or both pairs is. provided anotheroutwardly extending lug or nib 29. A convenient way to form this memberis to provide two spaced slits extending longitudinally of the bodsection and forcing outwardly the walls be tween the slits which provideshoulders 30 on the opposite sides of the lugs 29, and these lugs aremade of a width so that they may pass into the open channels 22' betweenthe folded portions 24 of the cap. These lugs may be of shapes otherthan that shown. For example, they may be similar to lugs 26 with theirshoulders extending longitudinally'of the shell.

In assembling the cap and body portions the free end of the body sectionis inserted in the skirt of the cap with the lugs 29 in anys-uitable'o'pen channels '22. The portion 31 of the body section willyield inwardly sufiicient to cause the lugs 2'6't0 pass over theportions 24, and then will spring outwardly to cause the cap and-shell.

of the port-ions 24, as shown in Fig. 6, and

will securely lock the cap and body sections together. The lugs 29 willpreferably be seated in diametrically opposite channels 22 and the sideshoulders will engage the sides of these channels to prevent relativeturning movements of the cap and body sections in either direction, andso will prevent movement of the lugs or nibs 26 into alignment with thechannels to permit the separation of The shoulder 21 in the cap is solocated as to lie adjacent the free end of the body section, asindicated in Fig. 1, to prevent this section rocking laterally in thecap and to limit'movement of the body section into the cap. If it isdesired to separate the 'cap and body section all that is necessary isto press inwardly the yieldable portion 31 which will remove the lugs 26carried thereby from engagement with the shoulders 23. Then the body orcap may be rocked laterally to withdraw these lugs from the cap and thecap and body may be easily separated.

it will be apparent that the skirt portion of the cap is in one piecewith the body portionthereof, and that a single thickness only isrequired, doing away with the extra enclosing ring which is now commonlyemployed in this type of device. This structure also gives a smoothplain outer surface to the-cap, giving the required neat and attractiveappearance. It will further be noted that if undue strain is placed onthe cap and body sections tending to separate them, the pull of the lugs26 on the shoulders 23 of the folded portions 24 will tend to drawtheseportions inwardly toward-the lugs 26 and the body portion, so thatinstead of tending-to draw away from these supporting shoulders 23 thisstrain tends to draw these supporting shoulders toward the base of thelugs 26 and increase the holding effect.

This, therefore, gives a very strong connection between the cap and bodysections which will safely sustain the considerable weight involved intheshades and domes used.

Having thus set forth the nature of my invention, what I claim .is:

1. A shell comprising a body "section and a cap section adapted fortelescoping engagement, one of said sections having its free edgesprovided withalt'ernate series of shallow and deep notches, 'said'e'd'gebeing folded upon itself to provide protected shoulders and channelsopen at both ends, the other section being provided with laterallyprojecting lugs to "engage said shoulders to secure the sectionstogether, and means to-enter one of said channels to prevent relativeturning movei'nents of said sections in either direction. I

2. A socket shell comprising telescoping cap and body sections, one ofsaid sections having its free edge provided with a series of spacedshallow and deep notches, said 7 free edge being folded on itselfcausing said notches to provide sharply defined protected shoulders andopen ended channels, and the other section being provided with laterallyextending lugs to engage with said protected shoulders to secure thesections together.

3. A shell comprising telescoping cap and body sections, said cap beingprovided with alternate series of deep and shallow notches in its freeedge and the portion between said deep notches being folded inwardlytoward the wall of the cap to provide channels open at both ends andrecesses having sharply defined inner shoulders, the body being providedwith laterally extending lugs to engage the shoulders in said recessesto prevent separation of the cap and body, and said body also havingother laterally extending lugs to enter in certain of the channels andengage the side edges thereof to prevent relative turning movementsbetween the cap and body.

4. A shell comprising telescoping cap and body sections, said cap havingits free edge portion provided With a series of spaced shallow and deepnotches, said free edge portion being folded on itself causing saidnotches to provide sharply defined recessed shoulders and open endedchannels, said cap being also provided with a shoulder spaced inwardlyfrom the free edge of said folded portion, said body section beingprovided with laterally extending lugs arranged to engage said recessedshoulders to secure the sections together, and the free edge of the bodysection being adapted to engage said spaced shoulder in the cap to limitrelative longitudinal movement of said sections.

5. A shell comprising telescoping cap and body sections, said capsection being provided with alternate series of deep and shallow notchesin its free edge and-the portions between said deep notches being foldedinwardly on. the body of the cap to provide a series of channels open atboth ends and an alternate series of sharply defined recessed shoulders,said cap being also provided with a shoulder spaced inwardly from thefree edges of said folded portions, said body section having laterallyextending lugs to engage said recessed shoulders to secure the sectionstogether and other lugs to engage the sides of the channels to securethe sections against relative turning movements, and the free edge ofsaid body section being adapted to engage said spaced shoulder to limitrelative longitudinal movement of said sections towards each other.

6. An enclosing shell for lamp sockets and similar devices comprising acap having series of spaced shallow and deep notches about its free edgeand the portions between said inner wall of the cap, and a body sectionadapted to have one end thereof inserted into said cap and carryingmeans to engage the free edges of said shallow notches to secure the capand body together.

7. A shell for electrical devices comprising a cap section having seriesof spaced deep and shallow notches about its periphery and the portionsbetween said deep notches folded inwardly toward the inner side of thecap to provide open channels and recessed shoulders, abody sectionhaving one end adapted to be inserted into the cap, said body sectionbeing provided with a notch leading from the endthereof providing ayieldable portion at one side thereof, said yieldable portion having alug to engage a recessed shoulder of said folded portions, the bodybeing also provided with another lug to engage a recessed shoulder ofsaid folded portions on the opposite side of the cap, and an additionallug on the body adapted to enter one of said channels to preventrelative turning movements between the cap and body in either direction.

In testimony whereof I afiix my signature.

HARVEY HUBBELL, J R.

